only question b, first chart is filled out and only there for reference needs, please fill in empty chart. thank you

Manager T. C. Downs of Plum Engines, a producer of lawn mowers and leaf blowers, must develop an aggregate plan given the forecast for engine demand shown in the table. The department has a regular output capacity of 135 engines per month. Regular output has a cost of $64 per engine. The beginning inventory is zero engines. Overtime has a cost of $114 per engine. 1 120 8 2 135 3 140 Month 4 5 120 125 6 125 7 132 Total 1,032 Forecast 135 Period 1 2 3 4 5 6 7 8 Total Forecast 120 135 140 120 125 125 132 135 1,032 Output Regular Overtime 120 135 135 120 125 125 132 135 1,027 0 0 5 0 0 0 0 0 5 0 0 0 0 0 0 Output - Forecast Costs Output Regular Overtime $ 7,680 8,640 7,680 8,000 8,000 8,640 0 0 8,640 570 9,210 0 0 0 8,448 0 8,448 0 $ 65,728 570 $ 66,298 $ 7,680 8,640 7,680 8,000 8,000 8,640 Total b. Compare the costs to a level plan that uses inventory to absorb fluctuations. Inventory carrying cost is $4 per engine per month. Backlog cost is $144 per engine per month. There should not be a backlog in the last month. Set regular production equal to the monthly average of total forecasted demand. Assume that using overtime is not an option. (Negative amounts should be indicated by a minus sign. Leave no cells blank - be certain to enter "O" wherever required. Round average inventory row, Inventory cost row, and Total row values to 1 decimal.) Period 2 3 4 5 6 8 Total Forecast 120 135 140 120 125 125 132 135 1,032 Output Regular Output - Forecast Inventory Beginning Ending Average Backlog Costs Output Regular Inventory Backorder Total